This paper deals with a new instrument invented for measuring indicated horsepower, indicated mean effective pressure and the maximum cylinder pressure of a Diesel engine. If an oscilloscope is used, this instrument can display a diagram of cylinder pressure vs time or cylinder volume on it. The feature of this instrument is that the pressure transducer utilizing the magnetostriction effect is mechanically tough and has very large output. The basic principle of the mean effective pressure measuring system is to compute electrically the area of the pressure curve against cylinder volume per cycle, and this computation is performed by integrating the product of cylinder pressure and derivative of cylinder volume with respect to time over the period of a cycle. Horsepower is obtained as a product of mean effective pressure and revolutional speed. The cylinder pressures picked up with the magnetostrictive pressure indicator are compared with the reference pressures obtained with a Farnbolo indicator, and it is verified that the values of both pressure indicators are in good agreement. On indicated mean effective pressure and indicated horepower, the readings obtained with the new instrument agree with the values obtained by means of measuring the area of the pressure vs volume curve with a planimeter within about three percent accuracy and the maximum cylinder pressure examined with a Henni indicator shows accuracy better than two percent. In Japanese.

  • Corporate Authors:

    Ship Research Institute, Tokyo

    38-1, 6-chome, Shinkawa, Mitaka-shi
    Tokyo,   Japan 
  • Authors:
    • HORI, Y
    • Tuzi, U
  • Publication Date: 1971-7

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00033655
  • Record Type: Publication
  • Source Agency: Ship Structure Committee
  • Files: TRIS
  • Created Date: Jul 28 1973 12:00AM